Fluorescent lamps have been in common usage for many years. Such lamps are typically used in commercial or residential lighting. However, they are also used in industrial lighting circumstances. For example, fluorescent lamps can be used as an illumination source in electronic inspection equipment and machine vision measurement devices. Precise electronic inspection equipment requires high amplitude, invariant light sources. A common problem with standard fluorescent lamps is the variation in light output and uniformity. In high temperature environments, the internal vapor pressure of fluorescent lamps will increase and as a result the efficiency of the lamps drops dramatically. Losses as high as 40% have been detected in high temperature environments. Moreover, material emitted from the cathodes deposit along the length of the tubes of the lamp. As a result, the lamp light output uniformity decreases where the deposits darken the interior of the tubes.